Light emitting diode (LED) lighting systems are becoming prevalent as replacements for older lighting systems. LED systems are an example of solid state lighting (SSL) and have advantages over traditional lighting solutions, such as incandescent and fluorescent lighting, because they use less energy, are more durable, operate longer, can be combined in multi-color arrays that can be controlled to deliver virtually any color light, and generally contain no lead or mercury. A solid-state lighting system may take the form of a lighting unit, light fixture, light bulb, or a lamp.
An LED lighting system may include, for example, a packaged light emitting device including one or more light emitting diodes (LEDs), which may include inorganic LEDs, which may include semiconductor layers forming p-n junctions and/or organic LEDs, which may include organic light emission layers. Light perceived as white or near-white may be generated by a combination of red, green, and blue (“RGB”) LEDs. Output color of such a device may be altered by separately adjusting the supply of current to the red, green, and blue LEDs. Another method for generating white or near-white light is by using a lumiphor such as a phosphor. Still another approach for producing white light is to stimulate phosphors or dyes of multiple colors with an LED source. Many other approaches can be taken.
One type of traditional lighting system is an incandescent bulb that typically comprises a wire filament or filaments supported in a glass enclosure. Wires extend between the bulb's Edison screw base and the filament to provide electric current from the bulb's base to the filament. The filament heats and glows to emit usable light. Incandescent bulbs typically have a base with an Edison connector, or other style of connector, that is connected to the enclosure where the enclosure may have a variety of shapes and sizes. Another type of traditional lighting system is a fluorescent bulb that typically comprises a tube containing a gas. An electric current excites the gas to produce short-wave ultraviolet light that causes a phosphor coating on the inside of the bulb to glow. Fluorescent lights typically have a form factor of an elongated tube with a pair of pins at each end of the tube that physically support the lamp in the fixture and deliver current to the lamp.